"He's slipped through the net once or twice where we got closer to him than he would have liked," Abdullah told CNN's Wolf Blitzer on Tuesday. "The Iraqis, Jordanians and coalition forces are working very hard to track him down -- and we're getting close."

The king said he based his assessment on "hard intelligence."

Al-Zarqawi is the Jordanian-born militant wanted for fueling the insurgency in Iraq and in connection with the beheadings of several Western hostages.

The king said the search is ongoing and al-Zarqawi is a difficult man to track "in very difficult circumstances."

Abdullah described al-Zarqawi as constantly on the move.

He also said al-Zarqawi is thought to be inside Iraq after fleeing Falluja ahead of the latest U.S.-led assault on the city.

"He's under pressure," Abdullah said.

The United States has offered a $25 million reward for the capture or killing of al-Zarqawi.

He is accused of leading a terrorist network inside Iraq that has carried out numerous attacks against Iraqi civilians and U.S. military personnel and has kidnapped and beheaded numerous hostages.

His group changed its name from Unification and Jihad to the Base of Jihad after al-Zarqawi recently pledged allegiance to Osama bin Laden, leader of al Qaeda, which is Arabic for "the base."

Abdullah said there is a link between al-Zarqawi and al Qaeda, but described it as a "loose association."

Abdullah has been in Washington this week, and met with President Bush on Monday.